Disclaimer

I will use the color coding scheme which has become common among Pathfinder build handbooks. Also note that many colored items are also links to the Paizo SRD.

Red: Bad, useless options, or options which are extremely situational.

Orange: OK options, or useful options that only apply in rare circumstances

Green: Good options.

Blue: Fantastic options, often essential to the function of your character.

Temporary Note: Paizo has recently discontinued support of their official SRD. From this point forward SRD links on RPGBOT.net will instead link to d20PFSRD.com. While Archive of Nethys is now Paizo's officially licensed partner for the purposes of serving the Pathfinder SRD, Archive of Nethys is a horribly designed website and it simply doesn't match d20PFSRD's ability to keep pace with published content and d20PFSRD's search functionality.

If you encounter any links which still point to the old SRD, please email me so that I can correct them. I also recently added a page explaining my supported content which you may find helpful. --September 15, 2018

Introduction

"Area Control Defender" is a term that I invented largely in a vaccuum, so in the case that it's meaning isn't immediately clear:

Area Control Defender: A character built to separate enemies from their allies by strategically controlling an area on the battlefield.

Experienced players will probably have a basic understanding of this concept. Using a reach weapon, Combat Reflexes, tripping, etc. are all parts of the equation. However, there is much more to the concept than just a couple of feats and guisarme. There are a dizzying number of options available to you, and there are some rules minutae to be discussed which will clarify exactly how and why this strategy works, and why it is so popular.

Rules

There are some complicated (and sometimes poorly written) rules concepts which you need to grasp in order to fully take advantage of the options available. Once we've got our heads around the rules, we'll dig into build options.

Before proceeding, read the rules on Attacks of Opportunity. AoO's will feature prominently in this guide. So prominently, in fact, that I'm abbreviating them to AoO's, though I generally try to avoid doing so in my other articles.

Reach Weapons and Diagonals

Note: Small and Medium creatures wielding reach weapons threaten all squares 10 feet (2 squares) away, even diagonally. (This is an exception to the rule that 2 squares of diagonal distance is measured as 15 feet.)

Pathfinder's Combat rules omit that note. Without this note, a medium creature with a reach weapon can't attack any space directly at a diagonal to them, thereby allowing enemies to walk totally unimpeded in and out of your reach.

This was clarified/fixed in this FAQ from 2014, promising that the fix would be added to the next round of errata. However, the fix never made it onto the SRD. Make absolutely certain to explain this to your DM. Without this clarification, the entire Area Control Defender concept falls apart unless you make yourself large.

Charging Against Reach Weapons

I've had this debate with my own games, so let me settle it here: Charging through a creature's reach does provoke an attack of opportunity. In the Actions in Combat table, "Charge" says "No" in the "Attack of Opportunity" column because no part of the Charge action provokes an attack of opportunity beyond the parts of the action that already do so. The important clarification is in the footnotes:

1 Regardless of the action, if you move out of a threatened square, you usually provoke an attack of opportunity. This column indicates whether the action itself, not moving, provokes an attack of opportunity.

The footnote makes the most important part of are control defense functional. If enemies could charge you and get inside your reach for free, the entire strategy would only work if enemies were actively trying to get past you. If they were happy to focus on you (which is a success by some measures), most of your build falls apart and you're left hugely vulnerable.

You can get two attacks against charging enemies if you prepare an action. This means that you can get double damage with weapons with the Brace property from the prepared action and use your attack of opportunity to trip them or something.

Remember that the AC penalty from charging applies as soon as the charge is declared, so your attacks of opportunity benefit from the AC penalty. Also remember that Combat Reflexes doesn't allow you to get multiple attacks of opportunity against the same target for leaving one of your threatened squares, so even if you've got massive reach you'll probably only get one AoO per target per turn unless you also trip them.

5-Foot Steps and Their Implications

At medium size without anything beyond a reach weapon, 5-foot steps present a serious problem. Enemies can move into your reach and stop (or be stopped), then on the following turn take a 5-foot step inside your reach, preventing you from hitting them with your fancy polearm. This then forces you to stap away to attack them, putting you in a perpetual retreat until one of you dies. At low levels this will be a major problem, but as you pick up feats (see the "Feats" section, below) you can collect some options which will prevent or mitigate this problem.

You can also use difficult to prevents 5-foot steps, but most area control defenders won't have easy access to effects which create it, so you'll need to depend on feats instead.

Reach Diagrams

Wile the official SRD omits them, d20PFSRD.com provides some excellent reach diagrams (you'll need to scroll half-way down the page). Humanoids and other creatures with humanoid-like anatomy use the "Tall" sizes, while quadrupeds like horses and other short, broad creatures like dragons and snakes use the "Long" sizes.

In case it's not immediately clear what those diagrams are portraying: the white area is the space that you occupy. The green area is your "natural" reach (the stuff you could punch). The red area is what you can reach with a reach weapon. If you are using a reach weapon, you can attack stuff in the red area but not in the green area.

Whips Above Medium Size

The whip weapon description includes the following text:

The whip is treated as a melee weapon with a 15-foot reach

At medium size, that's fine. At small size, that's probably still fine. Outside of that narrow band of sizes, it starts to fall apart. There are three possible interpretations of the how reach works with a whip, each of which we'll examine. If you care about rules minutae or need to explain this to your DM, read on. If you just want to know the answer, skip to "So what's the answer", below.

Strict RAW

All creatures have 15-foot reach with whips.

While this is the answer best supported by the rules text, it falls apart almost immediately when you begin to think about its implications. A colossal creature using a whip wouldn't be able to hit creatures which it could reach with its bare hands. Tiny and smaller creatures could use a whip that's clearly too long for them to weild effectively. If we somehow for a fine sized creature (as big as a fly) to use a whip, they would still have 15-foot reach. Imagine a fly whipping you from across a room.

+10 Method

All creatures extend their natural reach by 10 feet with whips.

This method is supported by exactly one piece of evidence: Balors. Balors are large, and have a whip with 20-foot reach. This means that at large size, whips give you as much reach as a polearm. This negates much of the usefulness of a whip, but one could argue that it makes sense if you consider the tensile strength of the weapon as you make it gradually larger. The idea of a whip large enough for a collosal creature like a giant which uses whole trees as weapons seems a bit far-fetched, but in a world where that giant exists it's hard to argue such strict adherence to real-world physics. Maybe collosal giants use whips made of dragon leather or something.

As we extend beyond the small to large size band, this interpretation faces the same issues as the Strict RAW interpretation. Flies still get to whip you from across the room, and colossal giants still can't reach the ends of their own arms.

x3 Method

All creatures triple their natural reach with whips.

This interpretation has no basis in the official rules text. However, it has the closest thing we have ever gotten to an official FAQ/Errata answer. According to Paizo Creative Direction James Jacobs, whips triple the creatures natural reach. Tiny and smaller creatures are still a weird case, and Jacobs suggest 10-foot whip reach for tiny creatures, which might still mean that flies can whip you from across a room.

Notably, this also makes the balor stats incorrect. Personally I think that this is fine. It's one bit of text in exactly one monster, and could be easily erratad if Paizo ever chose to officialy clarify whips.

So what's the answer?

Unclear, but I think the x3 method makes the most sense based on the evidence cited above.

Building an Area Control Defender

Traits

Few traits cater to Area Control Defenders, and the few available are poor. Fortunately, that leaves you room to put your traits toward other aspects of your build like compensating for poor saving throws or skills.

Bullied (Combat): I would only take this on a Monk, and even then it's not fantastic.

Fencer (Combat): Unless your DM considers a Naginata to be similar to a dagger or a sword, this is worthless. You need reach.

Tactician (Combat): The once per day limitation makes this really difficult to justify.

Classes and Archetypes

Nearly any class can play an area control defender since almost every class gets proficiency with the longspear (druids and wizards are the exceptions). I won't go into detail on every class and archetype here, but I'll cover those classes which are well suited to the role, and any archetypes which specifically contribute to the concept.

Alchemist: Limited to longspears by default, but a level dip into any one of several classes will get you a better reach weapon. I recommend fighter if you want a polearm, but if you want a whip go for Mysterious Avenger. Alchemists get a lot that works for are control defenders. Mutagen provides fantastic ability score buffs, and the alchemist's spell list includes lots of great options for improving your reach, including Enlarge Person, Long Arm, and a whole bunch of polymorph spells including monstrous physique (monstrous humanoids) and giant form which will allow you to continue using your awesome polearm and giving you better than large size, thereby increasing your reach far beyond what a fighter can do.

Barbarian: If you want to do things the hard way, go for Barbarian. You won't get bonus feats, but Rage will give you useful bonuses to your attacks and such which will be very helpful.

Bloodrager: Largely identical to the Barbarian, but access to spells provides an extra set of options for increasign your reach. Enlarge Person and Long Arm are both on the Bloodrager spell list, and they're two of the easiest options. The Abberant bloodline provides a permanent 5 foot increase to your reach at 4th level, which is amazing.

Brawler: Falling somewhere between the Monk and the Fighter, the Brawler should be a good option. Unfortunately, lack of access to reach weapons means that the Area Control Defender's most important tool is off the table.

Cavalier: Charging into combat can be a great way to get into position. Unfortunately, your choice of reach weapon almost certainly shouldn't be a lance due to its lack of useful properties like brace and trip. If you're fine losing the lance's bonus damage or losing the special properties, this can still be a workable option. Cavaliers even get a handful of bonus feats to help get you up and running.

Fighter: All of the feats you could ever want, and some archetypes which make good Area Control Defenders. Even without the archetypes, Fighter is an excellent choice. On top of that, fighters get access to several fighter-exclusive feats like Pin Down, and the Weapon Focus feat chain and the Weapon Training class feature both add crucial attack bonuses which improve your combat maneuvers.

Phalanx Soldier: Phalanx Fighting and Ready Pike are great for Area Control Defenders, the archetype's biggest gimick is using a polearm one-handed with a shield, which becomes largely pointless when you pick up an animated shield.

Polearm Master: Pole fighting is a trap: use armor spikes. Steadfast Pike and Polearm Training appear to stack, which will make your attacks extremely reliable. Step Aside totally resolves the 5-foot step issue, but doesn't come along until 17th level.

Magus: Magi get all of the same useful area control defender spells that alchemists get, but they have better offensive spell options which they can use in conjunction with their polearm shenanigans to further inhibit enemies. Access to teleportation spells like dimension door also means that you can teleport into position.

Monk: The Monk's bonus feats provide several essential options for Area Control Defenders including Combat Reflexes and Improved Trip. Monks don't get many options for reach weapons, but the Double-Chained Kama should do just fine. Unfortunately, Monks don't have full BAB so you may have trouble qualifying for some feats.

Monk, Unchained: Largely the same as the Monk, but no archetypes are available, and the BAB change makes it easier to qualify for feats.

Paladin: Several of the Paladin's spells allow you to taunt enemies or otherwise force them to attack you or remain inside your reach. The Adept Champion feat provides a way to get a massive boost to your CMB against smite targets. Plus, paladins are notoriously difficult to kill.

Oath Against Savagery: Holy Reach may be able to supplant Lunge, but personally I prefer not to chain a mechanic which is so central to a build to a daily resource. Hordebreaker is also fantastic, allowing you to skimp on Dexterity and Combat Reflexes.

Ranger: No options that cater to Area Control Defenders.

Swashbuckler: The Opportune Parry and Riposte deed is a neat trick, but can't be used with the polearms which area control defenders depend upon to do their jobs.

Mysterious Avenger: If you want to use a whip (which is a good option), taking a single level of Mysterious Avenger Swashbuckler is a great idea. It gets you proficiency with whips and the ability to use whips with Swashbuckler Deeds like Opportune Parry and Riposte. Whips can be difficult, but might be worth the effort. It also improves the Swordmaster's Flair dramatically (see Magic Items, below).

Warpriest: Some bonus feats, and you get to select them as though you were a fighter of the same level.

Feats

Antagonize: While not directly part of the Area Control Defender combat strategy, Antagonize can be an excellent way to complement your other feats. The Diplomacy option adds a small impedence which makes it harder for enemies to attack your allies, and the Intimidate option provides a forced "taunt" effect (one of very few such effects in the game). The diplomacy option is great as a fallback option when you don't have a better idea for how to spend your standard action for a turn. Move into position, and antagonize an enemy while you wait for enemies to engage you. The Intimidate option only lasts one round unless the target can't attack you that round (maybe they were tripped?), but you can extend it for a second round as an Immediate action. That's two rounds of an enemy forced to do nothing else but attempt to attack you, which is exactly what you want them to do. The Intimidate option only works once per day, unfortunately, but I've used it to force enemies to run past several of my allies, drawing them away from frail allies and provoking several AoO's in the process. Use traits to get Diplomacy or Intimate as class skills, and even with poor Charisma you should be able to use this reasonably well.

Combat Expertise: Prerequisite.

Improved Trip: +2 to CMB to trip. Combined with your weapon, that's a big advantage. You already won't need to worry about attacks of opportunity against most enemies since they can't usually reach you.

Greater Trip: Another +2 to trip, and the target provokes attacks of opportunity. Not only do you get a free attack, but so do your friends!

Combat Reflexes: Crucial. You'll need some Dexterity to fuel it, but 12 is fine to start if you're playing something MAD like a Paladin. You can always get a belt later.

Pin Down: Requires 11 levels of Fighter, but if you're already a fighter this solves the 5-foot step problem.

Stand Still: This is a fallback if you don't have the feats (or Intelligence) for Combat Expertise and Improved Trip. Both tripping and Stand Still use a Combat Maneuver Check, but tripping allows you to get +2 from the weapon and +2 from each of Improved and Greater Trip, followed by a free attack against an enemy who is now prone and will draw an additional AoO when it stands.

Dodge: Prerequisite. The AC bonus is niice since almost all are control defenders will be using a two-handed weapon and foregoing the AC bonus from a shield until they can get an animated shield.

Mobility: Prerequisite. You should very rarely see the effects of this feat, but sometimes running past a couple of enemies can get you into a really advantageous position.

Combat Patrol: Also requires Combat Reflexes, but I listed it here because I know you took Combat Reflexes. This is a confusing feat, but it's very good. It increases your reach much further than you could go otherwise, but the movement mechanic means that you may be running all over the place during other people's turns. The only restriction on this movement is that you can't move more than your speed before your next turn, so you can move around largely wherever you like and put enemies exactly where you want them within your reach.

Spring Attack: Occasionally useful, Spring Attack will allow you to avoid an attack of opportunity while moving past enemies to get into positon. Only take this if you plan to also take whirlwind attack.

Whirlwind Attack: Of all of the feats in this guide, this is one of the last ones you should take of the actually useful feats since it's a secondary gimick to your normal AoO shenanigans. Since area control defenders already invest heavily

Lunge: Extending your reach can be a great advantage, but it only lasts until the end of your turn. That means that you can't extend your area of control between turns, which is where area control defenders really shine. However, it's a fantastic complement to whirlwind attack.

Power Attack: More damage is always great, but for an Area Control Defender it's often much more important to hit reliably than to deal a bunch of damage. Remember that the penalty applies to your combat maneuver checks since they're attacks, and the decision lasts until the beginning of your next turn so you'll suffer the effects on your attacks of opportunity, too.

Pushing Assault: This could be useful to adjust enemies' positions inside your reach, especially if you're dealing with multiple enemies. However, if you use this incorrectly you may find yourself pushing enemies out of your own reach. If the enemy lacks ranged attacks and doesn't want to run away, that means willingly re-entering your reach and facing the associated attacks of opportunity where applicable. Your best use case for this is to push enemies far enough away that you can still hit them, but they can't hit you. If you're large, you want to place enemies 15 feet away at the inner edge of your polearm's reach. This prevents them from using Withdraw to get away, it prevents them from 5-foot stepping adjacent to you, and it encourages them to try charging you, thereby suffering a -2 penalty to AC and allowing you to more easily hit them with Stand Still or trip them.

Step Up: The word "adjacent" breaks this feat for us. If it said "a foe within reach", it would be great. But adjacent means in an adjacent square, so they would need to be 5-foot stepping away from you, which brings them into your polearm's reach. That's right where you want them, so using Step Up would actually handicap you.

Weapon Focus: A +1 attack bonus isn't very exciting, but you're going to be making lots of attacks, and the bonus applies to your CMB when you trip with your weapon.

Greater Weapon Focus: Another +1, but limited to figthers (and classes that pretend to be fighters for feats).

Whip Mastery: You've picked up proficiency with whips, Weapon Focus (whip), and Whip Mastery. You can now do with your whip what every other area control defender has been doing with a horsechopper and armor spikes. You have the advantage of not needing to maintain a set of armor spikes, but there are so many other ways to keep enemies out of spike range (many of which you want to take even with a whip) that this seems unnecessary.

Greater Whip Mastery: Area control defenders are all about holding down multiple enemies. Grappling a single enemy with your whip means that you're turning off your best trick so mildly annoy one enemy.

Weapons

Reach is an absolute must, so only reach weapons are mentioned here (with the exception of Armor Spikes).

Armor Spikes: They don't require the use of your hands, which means that you can use them while two-handing a polearm. This allows you to threaten the area inside your polearm's reach, turning your halo of pain into a circle of pain. It's expensive to enchant two weapons, so don't put a ton of resources into what is essentially a backup plan. Instead, get cheap armor spikes and do your best to never need them.

Natural Weapons: If you don't have proficiency with martial weapons, armor spikes won't be very effective. Natural weapons work just as well, though your hands are probably busy holding a weapon, so look for bite attacks, gore attacks, etc.

Martial Weapons

Bardiche: Essentially a glaive with different critical hits, and its resistant to sundering for some reason. Personally I like 19-20/x2 over x3 crits, so I would take a bardiche over a glaive, but neither option is a good choice.

Bec de corbin: Strictly better than the glaive, it adds Brace and a bonus to sunder some armor. That said, it's still terrible.

Bill: An extra +1 to AC when fighting defensively is a cute trick, but it's a shield bonus and won't stack with an animated shield. It also adds Disarm, which is nice from time to time.

Glaive: Garbage. Absolute garbage. It's a longspear with very sligthly better damage. Almost any other polearm is better.

Glaive-guisarme: Adds Brace and a bonus to knock people off of horses. I don't know why you would ever buy a glaive.

Guisarme: The go-to option for Area Control Defenders. Reach and Trip are all that you technically need, but if you look a little further you can find better options.

Hooked lance: Identidical traits and comparable damage to guisarme, but with x4 criticals instead of x3. Calling this a lance is confusing since it doesn't get any of the things that you want from a lance. If you want crits, use this. If you want bigger base damage, go for the horsechopper.

Horsechopper: A guisarme with a bigger damage die. It's bizzare that horsechoppers are so good considering horsechoppers are made almost exclusively by and for goblins instead of professional smiths making weapons for soldiers. If you want bigger base damage, use this. If you want crits, go for the hooked lange.

Lance: Unless you're a cavalier, skip the lance.

Longspear: The layman's polearm. Reach on a stick. Available to everyone except druids ande wizard, if you're not using your hands they should be holding a longspear in the off chance that an attack of opportunity might present itself. If you want to be a serious are control defender, you'll never use one of these, but you should encourage your allies to use them if their hands are otherwise empty.

Lucerne hammer: A bec de corbin with a bigger damage die and weaker crits. If you really want to use Vital Strike it might be worthwhile, but that's not the point of this guide. If you want to add Vital Strike to the mix, read my Practical Guide to Vital Strike.

Naginata: Unless you're a samurai, skip this.

Ranseur: A guisarme with Disarm instead of Trip. Trip is considerably better even without considering the Area Control Defender concept.

Rhomphaia: Fragile.

Tepoztopilli: Fragile.

Tri-point double-edged sword: Identical to glaives, and glaives are bad.

Exotic Weapons

Few exotic weapons are worth the feat, but if you have spare feats in your build you might find something interesting.

Double-chained kama: You give up the largely useless Grapple property and the ability to deal bludgeoning damage compared to the kusarigama, but the text explicitly allows you to use the double-chained kama to attack adjacent foes.

Flying blade: A greataxe with reach, and you get a bonus on the most common form of AoO in exchange for a penalty to every other attack with the flying blade. I don't think it's worth the trade, personally.

Kusarigama: Double doesn't matter, Monk is only useful if you're a Monk, and grapple won't matter for our purposes, but it has both reach and trip. You also have access to bludgeoning damage, though you'll need to enchant both ends of the weapon to keep the extra damage relevant. RAW, since it's a reach weapon you can't use the kama end as a non-reach weapon, but I think a reasonable GM would allow you to do so. If your GM won't, use a double-chained kama instead and complain frequently about how the kama you're holding magically reachs over 5 feet but you can't use it to scratch your own back.

Kyoketsu shoge: Reach is the only important piece that we get from the kyoketsu shoge and the Kusarigama adds Trip.

Mancatcher: Only works on small and medium targets. It's barely a weapon.

Whip: Whips are hard. They have reach and both trip and disarm, which is a unique advantage. They're also one-handed, leaving a free hand for a shield. However, they attack like a ranged weapon (they provoke AoO's), they deal nonlethal damage, and they can't affect enemies with armor or with +3 or better natural armor. Those are serious handicaps. You can remove the handicaps with the Whip Mastery feat, but it requires Weapon Focus first. If you count proficiency, you're likely looking at 3 feats to make them viable, and most people don't want to spend the feats to make that happen. If you really want to use a whip, take a level of Mysterious Avenger Swashbuckler and switch to fighter after that. The whip has two major advantages that make it worth the investment: they can attack adjacent enemies, and they give you 15 foot reach at medium size. How this reach changes above medium size is confusing, so read the "Whips Above Medium Size" section, above, if you haven't already.

Armor

Your choice of armor doesn't matter much beyond the usual balance between Dexterity and base AC bonus. However, getting something which supports armor spikes can provide a useful fallback option if enemies get inside your reach.

Spells

This section won't address every spell on your spell list, but it will point out some especially notable options.

1st-Level Spells

Long Arm: +5 ft. reach for minutes/level. Available to a huge number of spellcasters, including alchemists, bloodragers, and magi.

4th-Level Spells

6th-Level Spells

Magic Items

Most of your magic items will depend on your choice of blass, but a few especially useful items and enchantments cater very well to area control defenders.

Weapons

+X (+X): Normally a static enhancement bonus is a waste of gold beyond the requisite +1 before you can add named enhancements. However, it becomes extremely important for Area Control Defenders. You may only get one attack against a given target in an entire round, and if you don't make that attack it may mean that an enemy gets past you to attack your squishy allies. The bonus applies to your attack bonus and your CMB, so don't skimp on it. If you have someone in the party who can cast Greater Magic Weapon, buy them a Pearl of Power. A Pearl of Power 3 costs just slightly more than upgrading your weapon from +2 to +3, and the enhancement bonus will scale as your party levels without getting any more expensive.

Fortuitous (+1): As an area control defender, your entire gimmick is to fish for attacks of opportunity. If you're doing well, that turns this enhancement into a free extra attack every round. That's an extra chance to trip or use Stand Still or whatever you like if you mess up your first attack, and if you didn't mess up that first attack you can use it for damage.

Wondrous Items

Boots of Striding and Springing: The extra speed is very useful if you pick up Combat Patrol.

Longarm Bracers: +5 ft. reach as a swift action 3/day. If it were more uses per day I would say go for it, but 3 just isn't enough.

Pliant Gloves: +5 ft. reach as a swift action for 10 rounds per day. That's just not enough to justify the cost.

Quickrunner's Shirt: I recommend this item on a lot of builds. Probably too many, but it's honestly good enough to justify it. The bulk of the time you won't need this. Since you're not reliant on full attacks to do your job, you don't need a gimick to get into position before attack. Usually charging or just normal walking will be fine. But in those rare cases where you need to rapidly reposition, this could save your party's lives.

Swordmaster's Flair (Blue Scarf): Only works once per day unless you're a Swashbuckler and can fuel it with Panache, but it activates as a swift action and increases you're reach by 5 feet for 1 minute. You need to hold it in one hand, so you'll need to use a whip.

Permanent Spells

Enlarge Person: Absolutely crucial. You want as much reach as you can get, and this is an inexpensive way to get natural reach. The ability score penalties are a mixed bag, however, since the Dexterity penalty will inhibit Combat Reflex, but the Strength will improve your CMB and damage, and the size bonus to CMB is fantastic. Combined with a reach weapon and armor spikes, you can threaten 20 feet in any direction. Keep enemies at 15 feet